The present invention relates to a head mounted type equipment or head mounted apparatus, such as a head mounted display, and more particularly to a head mounted apparatus that includes an attachment or mount mechanism to be mounted on a user's head.
A head mounted display is widely used because of easy image viewing on a wide screen, easy formations of stereoscopic visions, and mobility with a user. A mount mechanism holds the head mounted display on the front head side and includes a portion compressed against the frontal region, and a portion compressed against the occipital region. The mount mechanism fits the head by moving forward the occipital-region compressing portion after these portions are positioned at the front and back of the head. An adjusting mechanism that adjusts an interval between the frontal-region and occipital-region compressing portions to the head size can be provided on the left and right sides or on the backside of the head.
The mount mechanism that includes the adjusting mechanism at both sides of the head is disclosed, for example, in Japanese Patent No. 3,576,985 (FIG. 1 etc. corresponding to U.S. Pat. No. 6,515,853).
The mount mechanism that includes the adjusting mechanism at the backside is disclosed, for example, in Japanese Patent No. 3,042,353 (FIGS. 2 and 3 etc.). The adjusting mechanism in this mount mechanism includes a rotating drum having a projection, a left band that extends from the left temporal region to the occipital region, and a right band that extends from the right temporal region to the occipital region. Each band has plural holes engageable with the projection of the rotating drum. Among the pair of bands, the holed portions oppose to each other with respect to the rotating center of the rotating drum. Thus, a rotation of the rotating drum would loosen or fasten both bands. In mounting the mount mechanism on the head, one hand grasps the mount mechanism and the other hand rotates the back rotating drum in the band fastening direction, fixing the head.
However, the mount mechanism disclosed in U.S. Pat. No. 3,576,985 is a type that adjusts the left and right adjusting mechanisms independently, causing different left and right adjusting amounts. In particular, an elastic band that holds the occipital-region compressing portion provides the left and right adjusting amounts with a large degree of freedom, causing the occipital-region compressing portion to laterally shift relative to the frontal-region compressing portion, and making the attachment unstable. In addition, in that case, a laterally asymmetrical force applied to the occipital region causes a user to feel uncomfortable. The adjusting mechanism using a ratchet mechanism problematically generates noises during adjustment, and its stepwise adjustments cannot provide sufficiently fine mount capability.
A big-head user attempting to put on the mount mechanism after a small-head user puts it on needs to arduously unlock the ratchet mechanism and retreat the occipital-region compressing portion. In addition, since the unlocking direction and the retreating direction of the occipital-region compressing portion are different, two steps operations are needed and lower the operability.
On the other hand, the mount mechanism disclosed in Japanese Patent No. 3,042,353 requires one hand to support the head mounted apparatus and the other hand to manipulate the adjusting mechanism, posing bad manipulating or mounting problems.